Seated person determination apparatus for vehicle seats

• US 6,662,138 B1
• Filed: 11/08/2000
• Issued: 12/09/2003
• Est. Priority Date: 11/09/1999
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Takafuji, Tetsuya, Suzuki, Tomoji
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): LAU, TUNG S
• Application Number:
  US09/707,767
• Time in Patent Office: 1,126 Days
• Field of Search: 702/173, 177/144, 280/735, 280/728, 701/45-49, 359/601
• US Class Current: 702/173
• CPC Class Codes: B60N 2/002 Seats provided with an occupancy detection means mounted therein or thereon detection means responsive to presence or absence of children B60N2/266
• CPC Class Codes: B60N 2/0244 with logic circuits
• CPC Class Codes: G01G 19/4142 for controlling activation of safety devices, e.g. airbag systems electrical circuits for triggering safety arrangements in case of vehicle accidents B60R21/015

Abstract

The present invention provides a seated person determination apparatus for a vehicle seat that accurately differentiates the type of person seated, or differentiates a person seated from an object such as a child seat. This is accomplished by utilizing the shape of the standard surface distribution of the load that simulates the shape of contact surface formed between the human buttocks and the surface of seat pad. Specifically, the present invention provides a seat sensor composed of the plurality of sensor portions placed in a seat pad of a vehicle seat distributed in a plane parallel with the surface of the seat. The load exerted on the surface of the seat by a person seated or an object placed on the seat is detected by the plurality of sensor portions of the seat sensor located in corresponding position.

Claims

1. A seated person determination apparatus for a vehicle seat, comprising:

a seat sensor composed of a plurality of sensor portions placed in a seat pad of the vehicle seat, the sensor portions being distributed along a plane parallel to a surface of the vehicle seat, wherein a load exerted on the surface of the vehicle seat by a seated person or an object placed on the vehicle seat is detected by the plurality of sensor portions as a detected load;

a calculating device that calculates a degree of conformity between a shape of a surface distribution of the detected load and a shape of a standard surface distribution of a load, wherein the shape of the standard surface distribution of the load simulates a shape of a contact surface formed by a buttocks of a person seated and the surface of the seat, wherein the degree of conformity is calculated as a child'"'"'s pattern correlation coefficient and an adult'"'"'s pattern correlation coefficient and uses a cross correlation method; and

a decision device that differentiates the type of person seated from an object placed on the seat according to a degree of conformity between the shape of the surface distribution of the detected load and the standard surface distribution of the load.

5. A seated person determination apparatus according to claim 1, further comprising:

a rate increase calculating device that calculates a rate of increase of a detected load for each sensor portion that increases as a position is moved from one side of a seat pad surface to another side of the seat pad surface in left and right direction; and

wherein the decision device makes the determination based on both the degree of conformity and the calculated rate of increase.

6. A seated person determination apparatus as claimed in claim 1, further comprising:

a sum calculating means for calculating a sum of each detected load of each sensor portion that shows movement of the seated person from opposite sides of the seat pad surface in a left and right direction toward its center in left and right direction, said means to calculate calculating in a range less than the prescribed load; and

the decision device makes the determination based on both the degree of conformity and the sum of the load calculated by the means to calculate the sum.

7. A seated person determination apparatus as claimed in claim 1, further comprising:

means to calculate the sum of each detected load out of the detected load of the plurality of sensor portions that shows movement of the seated person from opposite sides of the seat pad surface toward its center, on a surface parallel to the plane orthogonal to the surface of seat pad, wherein the means to calculate calculates in a range less than the prescribed load; and

wherein the decision device makes the determination based on both the degree of conformity and the sum of the load calculated by the means of calculating the sum.

2. A seated person determination apparatus for a vehicle seat, comprising:

a seat sensor composed of a plurality of sensor portions placed in a seat pad of the vehicle seat, the sensor portions being distributed along a plane parallel to a surface of the vehicle seat, wherein a load exerted on the surface of the vehicle seat by a seated person or an object placed on the vehicle seat is detected by the plurality of sensor portions as a detected load;

a calculating device that calculates a degree of conformity between a shape of a surface distribution of the detected load and a shape of a standard surface distribution of a load, wherein the shape of the standard surface distribution of the load simulates a shape of a contact surface formed by a buttocks of a person seated and the surface of the seat; and

a decision device that differentiates the type of person seated from an object placed on the seat according to a degree of conformity between the shape of the surface distribution of the detected load and the standard surface distribution of the load;

wherein

the degree of conformity is calculated as a child'"'"'s pattern correlation coefficient and an adult'"'"'s pattern correlation coefficient and uses a cross correlation method; and

the decision device determines whether the child'"'"'s pattern correlation coefficient or the adult'"'"'s pattern correlation coefficient matches a human area or an area of an object placed on the seat, said human area and the area of the object placed on the seat are established by matching a distribution of the correlation coefficients with a plurality of cases of human and objects placed on the seat.

3. A seated person determination apparatus for a vehicle seat, comprising:

a seat sensor composed of a plurality of sensor portions placed in a seat pad of the vehicle seat, the sensor portions being distributed along a plane parallel to a surface of the vehicle seat, wherein a load exerted on the surface of the vehicle seat by a seated person or an object placed on the vehicle seat is detected by the plurality of sensor portions as a detected load;

a calculating device that calculates a degree of conformity between a shape of a surface distribution of the detected load and a shape of a standard surface distribution of a load, wherein the shape of the standard surface distribution of the load simulates a shape of a contact surface formed by a buttocks of a person seated and the surface of the seat; and

a decision device that differentiates the type of person seated from an object placed on the seat according to a degree of conformity between the shape of the surface distribution of the detected load and the standard surface distribution of the load;

wherein

the degree of conformity is calculated as a child'"'"'s pattern correlation coefficient and an adult'"'"'s pattern correlation coefficient utilizing a cross correlation method; and

the decision device determines whether the child'"'"'s pattern correlation coefficient or the adult'"'"'s pattern correlation coefficient matches the adult'"'"'s area, child'"'"'s area, or an object placed on the seat area, wherein the adult'"'"'s area, child'"'"'s area and object placed on the seat area are established by matching a distribution of correlation coefficients with predetermined numbers of cases of adults, children and objects on the seat.

4. The seated person determination apparatus for a vehicle seat, comprising:

a calculating device that calculates a degree of conformity between a shape of a surface distribution of the detected load and a shape of a standard surface distribution of a load, wherein the degree of conformity is calculated as a child'"'"'s pattern correlation coefficient and a adult'"'"'s pattern correlation coefficient by using a cross correlation method;

a decision device that determines whether a child'"'"'s pattern correlation coefficient and an adult'"'"'s pattern correlation coefficient match an adult'"'"'s area or a child'"'"'s area, the adult'"'"'s area and the child'"'"'s area are established by matching a distribution of a correlation coefficients with a plurality of cases of adults and children seated on the seat.

8. A seated person determination apparatus for a vehicle seat, comprising:

a seat sensor composed of the plurality of sensor portions -placed in the seat pad of a vehicle seat, wherein the sensor portions are distributed in a plane parallel to the surface of the seat, the load exerted on the surface of the seat by a person seated or by an object placed on the seat is detected by the plurality of sensor portions of the seat sensor located in corresponding positions;

a conformity calculating device calculating a degree of conformity between the shape of the surface distribution of the load detected by the plurality of sensor portions mentioned above, and the shape of the standard surface distribution of the load, the shape of the standard surface distribution of the load simulates the shape of contact surface formed by the buttocks of the person seated and the surface of seat, wherein the degree of conformity is calculated as a child'"'"'s pattern correlation coefficient and an adult'"'"'s pattern correlation coefficient and uses a cross correlation method;

a detected load sum calculating device, out of the detected load of the plurality of sensor portions, that shows movement of the seated person from opposite sides of the seat pad surface toward its center, the calculation being made in a range less than the prescribed load;

a means to synthesize synthesized data that enable determination of whether the person seated is a child or adult, said data from the sum of the load calculated by the means of calculating the sum and the degree of conformity and

a decision device to determine whether the person seated is a child or adult, said detection means differentiating the child or adult from an object placed on the seat based on the synthesized data.

9. A seated person determination apparatus for a vehicle seat, comprising:

a seat sensor composed of the plurality of sensor portions placed in the seat pad of a vehicle seat, the sensor portions are distributed in a plane parallel to the surface of the seat, the load exerted on the surface of the seat by the person seated or object placed on the seat pad is detected by the plurality of sensor portions of the seat sensor located in corresponding positions;

a conformity calculating device calculating a degree of conformity between a shape of the surface distribution of the load detected by the plurality of sensor portions and a shape of the standard surface distribution of the load, wherein the shape of the standard surface distribution of the load simulates the shape of contact surface formed by the buttocks of the person seated and the surface of seat, wherein the degree of conformity is calculated as a child'"'"'s pattern correlation coefficient and an adult'"'"'s pattern correlation coefficient and uses a cross correlation method;

a detected load sum calculating device summing the sensor portions that show movement of the seated person from opposite sides of the seat pad surface toward its center on a surface parallel to the plane orthogonal to the surface of seat pad, wherein the detected load sum calculating device calculates in a range less than the prescribed load;

a data synthesizing device that enables determination of whether the person seated is a child or adult from the sum of the load calculated by the detected load sum calculating device and the degree of conformity; and

a decision device to determine whether the person seated is a child, adult, or object placed on the seat based on said synthesized data.

10. A seated person determination apparatus for a vehicle seat, comprising:

a seat sensor composed of a plurality of sensor portions placed in a seat pad of the vehicle seat, wherein the sensor portions are distributed in a plane parallel to a surface of the vehicle seat, the load exerted on a surface of the seat by a person seated is detected by the plurality of sensor portions of a respective sensor portion;

a conformity calculating device calculating a degree of conformity between a shape of a surface distribution of a load detected by the plurality of sensor portions and a shape of a standard surface distribution of a load, the shape of the standard surface distribution of the load simulates a shape of a contact surface formed by a buttocks of the person seated and the surface of seat, wherein the degree of conformity is calculated as a child'"'"'s Pattern correlation coefficient and an adult'"'"'s pattern correlation coefficient and uses a cross correlation method;

a detected load summing device that sums a load detected by each sensor portion that shows movement of the seated person from opposite sides of the seat pad surface toward the center of the seat pad surface, wherein the sum is calculated in a range less than the prescribed load;

a data synthesizing device that enables determination of whether the person seated is a child or adult from a sum of the load calculated by the detected load summing device and the degree of conformity; and

a decision device that determines whether the person seated is a child or adult based on synthesized data from the data synthesizing device.

11. A seated person determination apparatus for a vehicle seat, comprising:

a seat sensor having a plurality of sensor portions placed in a seat pad of the vehicle seat, wherein the sensor portions are distributed in a plane parallel to a surface of the vehicle seat, a load exerted on the surface of the seat by a person seated is detected by respective sensor portions;

a conformity calculating device calculating a degree of conformity between a shape of a surface distribution of the load detected by the plurality of sensor portions and a shape of a standard surface distribution of the load, the shape of the standard surface distribution of the load simulates the shape of contact surface formed by a buttocks of the person seated and the surface of seat, wherein the degree of conformity is calculated as a child'"'"'s pattern correlation coefficient and an adult'"'"'s Pattern correlation coefficient and uses a cross correlation method;

a detected load sum calculating device that sums a load of each sensor portion that shows increasing tendency as a position is moved from opposite sides of the seat pad surface toward a center of the seat pad on a surface parallel to a plane orthogonal to a surface of seat pad, a calculation being made in a range less than the prescribed load;

a data synthesizing device that enables determination of whether the person seated is a child or adult from the sum of the load calculated by the detected load sum calculating device and the degree of conformity; and

a decision device that determines whether the person seated is a child or adult based on said synthesized data.

12. A seated person determination apparatus for a vehicle seat, comprising:

a seat sensor composed of a plurality of sensor Portions placed in a seat pad of the vehicle seat, wherein the sensor portions are distributed in a plane parallel to a surface of the vehicle seat, the load exerted on a surface of the seat by a person seated is detected by the plurality of sensor portions of a respective sensor portion;

a conformity calculating device calculating a degree of conformity between a shape of a surface distribution of a load detected by the plurality of sensor portions and a shape of a standard surface distribution of a load, the shape of the standard surface distribution of the load simulates a shape of a contact surface formed by a buttocks of the person seated and the surface of seat;

a detected load summing device that sums a load detected by each sensor portion that shows movement of the seated person from opposite sides of the seat Pad surface toward the center of the seat pad surface, wherein the sum is calculated in a range less than the prescribed load;

a data synthesizing device that enables determination of whether the person seated is a child or adult from a sum of the load calculated by the detected load summing device and the degree of conformity; and

a decision device that determines whether the person seated is a child or adult based on synthesized data from the data synthesizing device;

wherein

the conformity calculating device calculates the degree of conformity from the shape of the standard surface distribution of the load and the shape of the surface distribution of the detected load, the degree of conformity is calculated as a child'"'"'s pattern correlation coefficient and an adult'"'"'s pattern correlation coefficient utilizing a cross correlation method; and

the data synthesizing device synthesizes synthesized data based on the sum of the load calculated by the detected load sum calculating device and the difference between the adult'"'"'s pattern correlation coefficient and the child'"'"'s pattern correlation coefficient.